CVE-2021-3697 – grub2: Crafted JPEG image can lead to buffer underflow write in the heap
https://notcve.org/view.php?id=CVE-2021-3697
A crafted JPEG image may lead the JPEG reader to underflow its data pointer, allowing user-controlled data to be written in heap. To a successful to be performed the attacker needs to perform some triage over the heap layout and craft an image with a malicious format and payload. This vulnerability can lead to data corruption and eventual code execution or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12. Una imagen JPEG diseñada puede conllevar que el lector de JPEG desborde su puntero de datos, permitiendo que los datos controlados por el usuario sean escritos en la pila. • https://bugzilla.redhat.com/show_bug.cgi?id=1991687 https://security.gentoo.org/glsa/202209-12 https://security.netapp.com/advisory/ntap-20220930-0001 https://access.redhat.com/security/cve/CVE-2021-3697 • CWE-787: Out-of-bounds Write •
CVE-2021-3695 – grub2: Crafted PNG grayscale images may lead to out-of-bounds write in heap
https://notcve.org/view.php?id=CVE-2021-3695
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12. Una imagen PNG en escala de grises de 16 bits diseñada puede conllevar a una escritura fuera de límites en el área de la pila. • https://bugzilla.redhat.com/show_bug.cgi?id=1991685 https://security.gentoo.org/glsa/202209-12 https://security.netapp.com/advisory/ntap-20220930-0001 https://access.redhat.com/security/cve/CVE-2021-3695 • CWE-787: Out-of-bounds Write •
CVE-2021-3669 – kernel: reading /proc/sysvipc/shm does not scale with large shared memory segment counts
https://notcve.org/view.php?id=CVE-2021-3669
A flaw was found in the Linux kernel. Measuring usage of the shared memory does not scale with large shared memory segment counts which could lead to resource exhaustion and DoS. Se ha encontrado un fallo en el kernel de Linux. La medición del uso de la memoria compartida no escala con grandes recuentos de segmentos de memoria compartida, lo que podría conllevar a el agotamiento de recursos y el DoS. • https://access.redhat.com/security/cve/CVE-2021-3669 https://bugzilla.redhat.com/show_bug.cgi?id=1980619 https://bugzilla.redhat.com/show_bug.cgi?id=1986473 https://security-tracker.debian.org/tracker/CVE-2021-3669 • CWE-400: Uncontrolled Resource Consumption CWE-770: Allocation of Resources Without Limits or Throttling •
CVE-2021-20316 – samba: Symlink race error can allow metadata read and modify outside of the exported share
https://notcve.org/view.php?id=CVE-2021-20316
A flaw was found in the way Samba handled file/directory metadata. This flaw allows an authenticated attacker with permissions to read or modify share metadata, to perform this operation outside of the share. Se ha encontrado un fallo en la forma en que Samba maneja los metadatos de los archivos/directorios. Este fallo permite a un atacante autenticado con permisos para leer o modificar los metadatos del recurso compartido, llevar a cabo esta operación fuera del recurso compartido. • https://access.redhat.com/security/cve/CVE-2021-20316 https://bugzilla.redhat.com/show_bug.cgi?id=2009673 https://bugzilla.samba.org/show_bug.cgi?id=14842 https://security-tracker.debian.org/tracker/CVE-2021-20316 https://security.gentoo.org/glsa/202309-06 https://www.samba.org/samba/security/CVE-2021-20316.html • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') •
CVE-2021-3975 – libvirt: segmentation fault during VM shutdown can lead to vdsm hang
https://notcve.org/view.php?id=CVE-2021-3975
A use-after-free flaw was found in libvirt. The qemuMonitorUnregister() function in qemuProcessHandleMonitorEOF is called using multiple threads without being adequately protected by a monitor lock. This flaw could be triggered by the virConnectGetAllDomainStats API when the guest is shutting down. An unprivileged client with a read-only connection could use this flaw to perform a denial of service attack by causing the libvirt daemon to crash. Se ha encontrado un fallo de uso de memoria previamente liberada en libvirt. • https://access.redhat.com/security/cve/CVE-2021-3975 https://bugzilla.redhat.com/show_bug.cgi?id=2024326 https://github.com/libvirt/libvirt/commit/1ac703a7d0789e46833f4013a3876c2e3af18ec7 https://lists.debian.org/debian-lts-announce/2024/04/msg00000.html https://security.netapp.com/advisory/ntap-20221201-0002 https://ubuntu.com/security/CVE-2021-3975 • CWE-416: Use After Free •